In the 3rd Generation Partnership Project (3GPP for short below), a carrier aggregation (CA for short below) technology is introduced, which means communication between a base station and a user equipment (UE for short below) may be implemented on at least two aggregated component carriers (CC for short below).
In a case where a CA technology is introduced, a UE needs to report uplink and downlink capabilities of the UE to a base station, where the uplink and downlink capabilities of the UE include a combination of frequency bands at which the UE concurrently supports transmission or reception of data.
The base station configures a carrier set for the UE according to the uplink and downlink capabilities reported by the UE. The UE measures and feeds back, on each carrier in the carrier set configured by the base station, reference signal received power (RSRP for short below)/reference signal received quality (RSRQ for short below), and the like. Further, the base station may also configure activation or deactivation of a supplementary carrier for the UE (a primary carrier of the UE is always activated); the UE measures channel state information (CSI for short below) on each carrier in an activated carrier set (including the primary carrier and an activated supplementary carrier), and receives, according to a received physical downlink control channel (PDCCH for short below), a physical downlink shared channel (PDSCH for short below) on a part or all carriers in the activated carrier set.
In the prior art, the base station can only select an activated carrier set for the UE according to long term statistics information RSRP/RSRQ fed back by the UE, and therefore the manner of selecting an activated carrier set by the base station for the UE is not flexible enough.